Endoscopic surgery (also called keyhole surgery) encompasses modern, minimally invasive surgical procedures, in which access to the surgical field is gained through relatively small incisions. Endoscopic surgery includes laparoscopic procedures, which are performed within the abdominal or pelvic cavities. Endoscopic surgery also includes thoracoscopic procedures, which are performed on the thoracic or chest cavity.
Minimally invasive surgical procedures are desirable because they make possible reduced blood loss; reduced post-operative patient discomfort; shortened recovery and hospitalization time; and reduced exposure of internal organs to possible contaminants.
In laparoscopic surgery, for example, operations in the abdomen are performed through relatively small incisions (usually 0.5-1.5 cm).
During laparoscopic surgery, the abdomen is inflated using CO2 gas provided by an insufflation circuit. The CO2 elevates the abdominal wall above the internal organs like a dome to create a working and viewing space for the surgery.
One key element in laparoscopic surgery is an assembly called a laparoscopic trocar (which, in short hand, will be called an “LT”). A conventional LT 10 is shown in FIGS. 1A and 1B. The LT 10 is an access device used to penetrate the wall of the abdominal cavity to provide access for the introduction of CO2 insufflation gas; the manipulation of surgical instruments; and the insertion of optics (called laparoscopes) to observe the operating field while surgery is performed. A conventional LT 10 is typically treated as a single use, disposable item.
A conventional LT 10 consists of two parts (see FIG. 1A): a cannula 12 and an obturator 14.
The cannula 12 is a tubular sleeve that defines an access path or lumen to the operating field. The cannula typically includes a self-contained “air-lock” mechanism within the lumen, which provides access for surgical instruments and optics through the cannula, while preventing the escape of CO2 introduced into the abdominal cavity, so the cavity stays inflated.
According to existing laparoscopic surgical preference and practice, conventional laparoscopic surgical instruments and laparoscopes are typically sized and configured in one of three standard exterior diameters, the smallest being about 5 mm, the next larger being about 10 mm, and the largest being about 12 mm. Due to inventory and cost issues, the conventional LT's incorporate cannulas 12 accordingly sized in a range of standard interior diameters to accommodate the smooth and airtight passage of the conventional 5 mm, or 10 mm, or 12 mm instruments. This hierarchy of cannula sizes for conventional LT's imposes limitation upon the use of specialized instruments having desirable added functional benefits, but which increase the exterior diameter of the instrument.
The obturator 14 is an elongated pointed cylinder with a sharpened, tissue-penetrating tip. The obturator 14 is sized and configured to fit within the lumen of a conventionally-sized cannula 12, with the penetrating tip 16 protruding from the open end of the cannula lumen, as FIG. 1B shows. The protruding, penetrating tip 16 of the obturator 14 incises or separates tissue on entry so as to allow body penetration.
In conventional usage, the LT 10 is supplied as an assembled unit, as shown in FIG. 1B, including the cannula 12 and a dedicated obturator 14 inserted through the lumen of the cannula. To penetrate the abdominal wall, the surgeon manipulates the cannula 12 and dedicated obturator 14 as a single assembled unit (see FIG. 1C). Once penetration has been made, the dedicated obturator 14 is withdrawn (see FIG. 1D), opening the lumen of the cannula 12 for passage of instruments or optics.
Since conventional LT's are typically treated as single use items, after each obturator 14 is withdrawn from its companion cannula 12 as just described, the obturator 14 is not used again during the procedure. It is discarded as medical waste. Theoretically, an obturator 14 (and companion cannula 12) could, if desired, be reprocessed for use in a subsequent procedure, but, according to conventional wisdom, many surgeons and surgical teams nevertheless resist reusing devices intended for single use that, even though reprocessed, have been inside a previous patient.
Typically, during a single laparoscopic procedure, several, separate LT's (each comprising a cannula 12 and its own dedicated obturator 14) are inserted (see FIG. 1E). For example, at least one LT 10 is inserted for the introduction of CO2 insufflation gas (the cannula 12 includes a stopcock 18 communicating with a passage in the cannula 12, to which an insufflation line can be coupled); one or more LT's are inserted for passage of surgical instruments; and at least one LT is inserted for the passage of a laparoscope. The separate LT's (each comprising a cannula 12 and its dedicated obturator 14) are inserted individually, one at a time, in sequence, to provide the desired number of abdominal penetrations; and, in sequence, the withdrawn obturators 14 are put aside, one at a time, for disposal. Thus, at the end of the procedure (see FIG. 1E), the number of obturators 14 that are discarded as medical waste equals the number of cannulas 12 that form the abdominal penetrations.